Characterization of antibiotic pharmaceutical formulation containing Baccharis extracts

Abstract

Baccharis incarum (Wedd.) Perkins (syn.: Baccharis tola Phil.) known under the popular names of lejia, tola and baila buena is common in the arid Andean at 3,800 meters above sea level in Antofagasta de la Sierra, Catamarca, Argentina. Previous phytochemical studies on the leaves and top parts (aerial parts) of B. incarum described the isolation of chlorogenic acid and flavones. The anti-inflammatory, antioxidant, anti-xanthine oxidase effect and antibacterial activity on antibiotic resistant Gram positive and Gram negative bacteria were demonstrated in B. incarum ethanolic extract. The aim of the present work was to obtain an antibiotic pharmaceutical formulation containing B. incarum ethanolic extract. The tincture was incorporated in a topical pharmaceutical formulation (hydrogel). The hydrogel containing Baccharis extract showed microbiological, physical and functional stability during storage for 90 days. The preparation was active against antibiotic-multi-resistant Gram negative and Gram positive bacteria and was not genotoxic by Salmonella typhimurium assays. Studies which measure the drug release as determination of bioavailability were also carried out using the Franz diffusion cell. By HPLC analysis, two compounds (chlorogenic acid and 4?, 5-dihydroxy-3?, 3, 6, 7, 8-pentamethoxyflavone) were identified in the tincture and in the receptor solution of the Franz diffusion cell. The flavone showed also antimicrobial activity. The results obtained demonstrated that some natural compounds with antibacterial activities from B. incarum are released from the pharmaceutical formulations and this preparation could be used as topic antibiotic.